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Coffinfishes, seatoads, gapers

John H. Caruso and Theodore W. Pietsch
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taxon links [down<--]Lophiiformes Interpreting the tree
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Containing group: Lophiiformes


The chaunacids are one of the more recognizable lophiiform families, with large globose heads, a conspicuous network of open sensory canals, and a single open lateral–line canal extending posteriorly along a moderately compressed trunk and tail. The angling apparatus consists of a short illicium with a terminal esca comprised of a dense cluster of short cirri. The family contains two genera and 15 species. Chaunacids live a benthic lifestyle at depths ranging from 90 to over 2000 m. Researchers at the College of Charleston recently captured a red-eyed gaper (Chaunax stigmaeus) on video sitting on the seafloor off South Carolina, U.S.A.

Chaunacids are occasionally caught as bycatch in commercial fishery operations; however, with the exception of some regions in eastern Asia, chaunacids are not marketed for human consumption.


Body rounded and very slightly compressed, with very loose, flaccid skin; body tapering to a small rounded tail. Head very large and globose, roughly cuboid and bearing especially prominent open lateral-line canals; eyes dorsolateral and covered with a clear ‘window’ of skin; mouth large, oblique to nearly vertical, with relatively small, sharp slender teeth. Illicium short, located just behind snout in front of an ovoid, scaleless patch of skin, or within a depression into which it can be retracted; esca mop-like, a dense cluster of numerous, short, thread-like cirri; two additional cephalic dorsal-fin spines present as embedded vestiges, postcephalic dorsal-fin spines absent; soft dorsal fin with 10 to 12 rays, anal fin with 5 to 7 rays, pectoral fins narrow and paddle-like, with 10 to 15 soft rays. Skin densely covered with small to minute spine-like scales that are somewhat similar both in shape and feel to placoid scales of some sharks. Single open lateral-line canal on body joining conspicuous canals on head and extending posteriorly to proximal portion of caudal fin; lateral line proper with 17 to 42 neuromasts (Caruso, 1989a, b).

Color generally pink, reddish, orange, or rose-colored; some species with pale diffuse spots of yellow or olive green.

Key to the Genera of the Chaunacidae

1A. Anal-fin rays 5 or 6 (usually 6); greatest distance between anterolateral angles of sphenotic bones (prominent bumps beneath skin behind eyes) 22 to 27% of standard length; 9 neuromasts in supraorbital row (A-B), 1 neuromast in upper preopercular row (B-C), 2 in lower preopercular row (C-D), 3 in pectoral row (D-E), 17 to 21 in lateral line (B-F) (Chaunacops Caruso, 1989b)

1B. Anal-fin rays 6 or 7 (usually 7); greatest distance between anterolateral angles of sphenotic bones (prominent bumps beneath skin behind eyes) 15 to 23% of standard length; 10 to 13 neuromasts (usually 11) in supraorbital row (A-B), 2 to 4 neuromast in upper preopercular row (B-C), 3 to 5 in lower preopercular row (C-D), 10 to 13 in pectoral row (D-E), 29 to 42 in lateral line(E-F) (Chaunax Lowe, 1849)

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© 2005

Other Names for Chaunacidae


Caruso, J. H. 1989a. Systematics and distribution of the Atlantic chaunacid anglerfishes (Pisces: Lophiiformes). Copeia, 1989(1):153-165.

Caruso, J. H. 1989b. A review of the Indo-Pacific members of the deep-water chaunacid anglerfish genus Bathychaunax, with the description of a new species from the eastern Indian Ocean (Pisces: Lophiiformes). Bull. Mar. Sci., 45(3):574-579.

Lowe, R. R. 1849. On a new genus of the family Lophiidae (les Pectorales Pédiculées, Cuv.) discovered in Madeira. Trans. Zool. Soc. Lond., 3:339-344.

Caruso, J. H., H.-C. Ho, and T. W. Pietsch. 2006. Chaunacops Garman, 1899, a senior objective synonym of Bathychaunax Caruso, 1989 (Lophiiformes: Chaunacoidei: Chaunacidae). Copeia, 2006(1): 120-121.

Title Illustrations
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Scientific Name Chaunax sp.
Specimen Condition Dead Specimen
Identified By J. Randall
Copyright © 2007 J. Randall
About This Page

Tulane University, New Orleans, Louisiana, USA

Theodore W. Pietsch
University of Washington, Seattle, Washington, USA

Correspondence regarding this page should be directed to Christopher P. Kenaley at and Theodore W. Pietsch at

Page: Tree of Life Chaunacidae. Coffinfishes, seatoads, gapers. Authored by John H. Caruso and Theodore W. Pietsch. The TEXT of this page is licensed under the Creative Commons Attribution-NonCommercial License - Version 3.0. Note that images and other media featured on this page are each governed by their own license, and they may or may not be available for reuse. Click on an image or a media link to access the media data window, which provides the relevant licensing information. For the general terms and conditions of ToL material reuse and redistribution, please see the Tree of Life Copyright Policies.

Citing this page:

Caruso, John H. and Theodore W. Pietsch. 2007. Chaunacidae. Coffinfishes, seatoads, gapers. Version 02 October 2007 (under construction). http://tolweb.org/Chaunacidae/21997/2007.10.02 in The Tree of Life Web Project, http://tolweb.org/

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